Iron Isotopes The mass spectrometer can be used to determine the relative atomic mass of iron, and it’s isotopic composition. Iron has 26 Protons, 26 electrons and 30 neutrons. Continuous Spectrum Shows all wavelengths of visible light Emission Lines Colored lines on black background (certain wavelengths visible) Absorption Lines Black lines on colored background (certain wavelengths missing) NUCLEAR SYMBOLS: 57 Fe 26 56 Fe 26 54 Fe 26 Every element has their own combination of orbital jumps, therefor every element has their own unique emission spectrum. When iron is heated some electrons in orbitals near the nucleus will absorb enough energy to allow them to jump to new orbitals. Electrons will rid itself of any excess energy in photons, which means they give off light. The isotopes of Iron (Fe) are: • Fe 54 (6.4%) • Fe 56 (100%) • Fe 57 (2.3%) The relative abundance of an isotope means the percentage of
that particular isotope that occurs in nature. As you can see
Relative atomic mass of Iron:
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Fe 54 6.4 Fe 56 100 Fe 57 2.3 100 + 6.4 + 2.3 = 108.47 typical atoms (6.4 x 54) + (100 x 56) + (2.3 x 57) = 6076.7 6076.7 / 108.47 = 56.022 (3 d.p) 56.022 is the relative atomic mass of Iron.